In the past we would package both single and dual into the same update, as of right now I would recommend loading the Dual and keeping the printer up to date with its inherent code. I do not have reason to believe loading the single extrusion will cause any issues with the printer.

The difference between single and dual firmware is whether detecting the right side temperature or not.If you want to keep the right side thermocouple, then dual firmware.If you want to remove the right side thermocouple, then single firmware. And you will lose the heating function for right side together.